Integral image readin/writing head, image processor provided with this, image reading head and print head

ABSTRACT

An image read/write head (A) includes a support ( 7 ) for supporting at least one of paired platen rollers (P 1 , P 2 ) and a detector ( 2 ) for detecting at least one of a document (D) and a recording paper (K). Therefore, an image processing apparatus incorporating the image read/write head (A) can be easily manufactured. The image read/write head (A) further includes a reflection preventing member ( 6 ) for collectively surrounding the plurality of light receiving elements ( 3 ) and the plurality of drive IC chips ( 80 ). Therefore, it is possible to prevent the plurality of light receiving elements from receiving scattering light or disturbing external light.

TECHNICAL FIELD

The present invention relates to an image read/write head having both animage reading function and an image printing function, and an imageprocessing apparatus incorporating such a image read/write head. Thepresent invention also relates to an image read head having an imagereading function and a printhead having an image printing function.

BACKGROUND ART

Examples of image processing apparatus include a facsimile machine. Afacsimile machine needs to have both an image reading function and animage printing function. Further, it is desired that a facsimile machineis so structured to have a size as small as possible.

Therefore, a prior art image read/write head H has the structure asshown in FIG. 15. The image read/write head H includes a case 1 e and atransparent cover 19 e mounted on an upper portion of the case. The headcase 1 e accommodates light sources 30 e for illuminating an imagereading line Se defined on a surface of the transparent cover 19 e, andlenses 5 e. A substrate 4 e is mounted at the bottom of the case 1 e.The substrate 4 e has an obverse surface 40 and a reverse surface 41respectively provided with a plurality of light receiving elements 3 eand a plurality of heating elements 8 e in respective rows extendinglongitudinally of the substrate 4 e. On the reverse surface 41 of thesubstrate 4 e are also mounted a plurality of drive IC chips 80 eincorporating driving circuits for providing drive control of theheating elements 8 e.

With such an image read/write head H, a document D is transferred by aplaten roller P₁ in close contact with the obverse surface of thetransparent cover 19 e. During the transferring step, a surface of thedocument D is illuminated by the light sources 30 e. The light reflectedby the document D is collected by the lenses 5 e, thereby forming animage of the document D on the light receiving elements 3 e, whichoutput image signals. On the other hand, a recording paper K ofheat-sensitive type is transferred by a platen roller P₂ in closecontact with the heating elements 8 e. During the transferring step, thedriving circuits in the drive IC chips 80 e drive selected ones of theheating elements 8 e for heat generation. As a result, an image isprinted on the recording paper K. The facsimile machine incorporatingthe image read/write head H can be made smaller in thickness than afacsimile machine in which a reading head and a printing head areseparately provided.

However, the above-described prior art structure has the followingproblems.

Firstly, as described above, the image read/write head H is used incombination with a pair of platen rollers P₁ and P₂ for a document and arecording paper, respectively. Therefore, it is desired that the imageread/write head H has such a structure as to allow easy positioning andmounting of the platen rollers P₁ and P₂ relative to the imageread/write head. However, the prior art image read/write head H does notinclude such positioning or mounting means, which is inconvenient.

Secondly, the platen rollers P₁, P₂ are disposed so as to sandwich theimage read/write head H, so that the image read/write head H incombination with the platen rollers P₁ and P₂ becomes bulky in thethickness direction of the image read/write head.

Thirdly, in manufacturing the image read/write head H, after a pluralityof light receiving elements 3 e are mounted on an obverse surface 40 ofa substrate 4, the substrate needs to be turned over for mounting aplurality of heating elements 8 and a plurality of drive IC chips 80 ona reverse surface 41 of the substrate 4. Moreover, wiring patterns withrespect to these components also need to be provided on both the obverseand the reverse surfaces 40, 41 of the substrate 4. Therefore, the imageread/write head H cannot be efficiently manufactured.

Fourthly, there is a likelihood that the light receiving elements 3 ereceive inappropriate light which may cause noises. Specifically, withthe above-described prior art structure, the light passing through thelenses 5 e may be reflected in a scattering manner by the wall surfacesaround the light receiving elements 3 e, and the scattering light may bereceived by the light receiving elements 3 e. Moreover, light fromoutside the case 1 e may enter the case 1 e through a small gap definedbetween the case 1 e and the substrate 4 e to be received by the lightreceiving elements 3 e.

Fifthly, with the prior art image read/write head H, it is impossible todetermine whether or not the document D is fed onto the transparentcover 19 e. Similarly, it is also impossible to determine whether or notthe recording paper K is fed on the heating elements 8. Therefore, asindicated by phantom lines in FIG. 15, sensors 99 a, 99 b for detectingthe presence or absence of the document D and the recording paper K,respectively, need to be provided separately from the image read/writehead H. With such an arrangement, the sensors 99 a, 99 b and the imageread/write head H need to be individually mounted at respectivepositions, which makes the manufacturing process of an image processingapparatus troublesome. Further, the image reading operation may becontrolled to be interrupted when the document D is advanced by apredetermined distance after the trailing edge of the document D isdetected by the sensor 99 a. In such a case, it is necessary toprecisely set the distance between the sensor 99 a and the image readingline Se of the image read/write head H, which is also troublesome.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to eliminate or reduce problemsof the prior art described above.

In accordance with a first aspect of the present invention, there isprovided an image read/write head comprising a substrate which carries aplurality of light receiving elements, a plurality of printing elementsand a plurality of drive IC chips incorporating driving circuits forproviding drive control of the printing elements, a case mounted on thesubstrate for surrounding the plurality of light receiving elementswhile avoiding the plurality of printing elements, a transparent covermounted to the case for contact with a document being transferred, alight source disposed in the case for illuminating the document, and aplurality of lenses disposed in the case for forming, on the pluralityof light receiving elements, an image of the document illuminated by thelight source. The image read/write head further includes supportingmeans for supporting a platen roller disposed in facing relationship toat least either one of the transparent cover and the plurality ofprinting elements.

With such a structure, by supporting the platen roller by the supportingmeans, the platen roller can be easily positioned relative to the imageread/write head. Further, it is also possible to facilitate the mountingof the platen roller.

Preferably, the case and the supporting means may be integrally moldedof resin.

With such a structure, it is possible to prevent the number of parts ofthe image read/write head from increasing, so that the productionefficiency of the image read/write head can be prevented from beingdeteriorated.

Preferably, each of the printing elements may comprise a heatingelement. The substrate may be mounted to a heat sink plate, and part ofthe heat sink plate may provide the supporting means.

With such a structure, heat generated at the heating elements can beallowed to dissipate through the heat sink plate to the outside.Therefore, it is possible to prevent the heating elements from beingoverheated, thereby enhancing the quality of printed images. Since thesupporting means is provided by utilizing the heat sink plate, anotherpart for providing the support means need not be provided. Therefore, itis possible to prevent the number of parts from increasing.

Preferably, the plurality of light receiving elements, the plurality ofprinting elements and the plurality of drive IC chips may be mounted ona same surface of the substrate.

With such a structure, unlike the above-described prior art, mounting ofthe light receiving elements, the printing elements, the drive IC chipscan be performed without turning over the substrate. Further, a wiringpattern with respect to the above-described elements and the drive ICchips can also be formed on the same surface of the substrate, so thatthe production efficiency of the image read/write head can be enhanced.Moreover, the pair of platen rollers for a document and a recordingpaper, respectively, can be arranged so as not to sandwich the imageread/write head in the thickness direction thereof. Accordingly, it ispossible to accomplish thickness reduction of the image read/write headcombined with the pair of platen rollers.

Preferably, the light receiving elements may be integrally built in thedrive IC chips.

With such a structure, it is possible to decrease the number of partsmounted on the substrate, so that the production efficiency of the imageread/write head can be enhanced.

In accordance with a second aspect of the present invention, there isprovided an image processing apparatus comprising an image read/writehead and a pair of platen rollers for a document and a recording paper,respectively. The image read/write head includes a substrate whichcarries a plurality of light receiving elements, a plurality of printingelements and a plurality of drive IC chips incorporating drivingcircuits for providing drive control of the printing elements, a casemounted on the substrate for surrounding the plurality of lightreceiving elements while avoiding the plurality of printing elements, atransparent cover mounted to the case for contact with a document beingtransferred, a light source disposed in the case for illuminating thedocument, and a plurality of lenses disposed in the case for forming, onthe plurality of light receiving elements, an image of the documentilluminated by the light source. The image read/write head furtherincludes supporting means for supporting at least one of the pairedplaten rollers.

With the image processing apparatus having the above-describedstructure, the same advantages as those obtained by the first aspect ofthe present invention can be obtained.

Preferably, each of the platen rollers may be held by a member providedseparately from the image read/write head, and the supporting means maybe fitted on a shaft portion of the recording paper platen roller forallowing pivotal movement of the image read/write head about the shaftportion. The image read/write head may be biased by an elastic member ina pivotal direction for pressing the transparent cover against thedocument platen roller.

With such a structure, it is possible to position the recording paperplaten roller relative to the image read/write head. The recording paperplaten roller can be easily and precisely arranged at an appropriateposition relative to the printing elements. Moreover, by utilizing theelastic force of the elastic member, the transparent cover can bepressed against the document platen roller with an appropriate force.Therefore, the document can be appropriately transferred as pressedagainst the transparent cover by the document platen roller.

In accordance with a third aspect of the present invention, there isprovided an image read/write head comprising a substrate which carries aplurality of light receiving elements, a plurality of printing elementsand a plurality of drive IC chips incorporating driving circuits forproviding drive control of the printing elements, a case mounted on thesubstrate for surrounding the plurality of light receiving elementswhile avoiding the plurality of printing elements, a transparent covermounted to the case for contact with a document being transferred, alight source disposed in the case for illuminating the document, and aplurality of lenses disposed in the case for forming, on the pluralityof light receiving elements, an image of the document illuminated by thelight source. The plurality of light receiving elements, the pluralityof printing elements and the plurality of drive IC chips are mounted ona same surface of the substrate. The image read/write head furtherincludes a reflection preventing member provided separately from thecase for collectively surrounding the plurality of light receivingelements and the plurality of drive IC chips.

The image read/write head having the above-described structure has thefollowing advantages.

Firstly, since the light receiving elements are surrounded by thereflection preventing member, it is possible to prevent the lighttraveling from the document to the light receiving elements from beingscattered and reflected around the light receiving elements. Further,since the reflection preventing member also blocks external light, it ispossible to prevent the light receiving elements from receiving suchexternal light. Therefore, a high image reading quality with littlenoise can be provided. Particularly, in the present invention, thereflection preventing member is provided separately from the case.Therefore, it is possible to select an optimum reflection preventingmember of a configuration, size, material and color suitable for theprevention of light reflection and the blocking of light.

Secondly, since the reflection preventing member collectively surroundsthe light receiving elements and the drive IC chips, mounting of thereflection preventing member can be performed easily and reliably.Specifically, to surround the light receiving elements separately fromthe drive IC chips by a reflection preventing member, the reflectionpreventing member needs to be made small, so that the handling thereofbecomes difficult. Further, in such a case, the reflection preventingmember is likely to come into contact with the drive IC chips and thelight receiving elements. When wires are bonded to the drive IC chipsand the light receiving elements, the reflection preventing member mayalso come into contact with the wires, thereby causing breakage of thewires. This problem is more likely to occur in the case where the driveIC chips and the light receiving elements are arranged close to eachother for reducing the size of the image read/write head. According tothe present invention, however, the light receiving elements and thedrive IC chips are collectively surrounded by the reflection preventingmember, the above-described problems are less likely to occur.

Thirdly, since the light receiving elements, the printing elements andthe drive IC chips are mounted on the same surface of the substrate, thesame advantages as those obtained by the first aspect of the presentinvention can be obtained. That is, the mounting of the respectiveelements and the drive IC chips, and the provision of the wiring patternwith respect to these components can be performed easily, which leads toenhancement of the production efficiency. Further, it is possible toreduce the total thickness of the image read/write head in combinationwith the paired platen rollers.

Preferably, the reflection preventing member may be black.

With such a structure, the reflection preventing member can absorb lightreaching thereto so that it is possible to more reliably prevent lightfrom scattering and reflecting.

Preferably, the reflection preventing member may include mounting meansfor positioning and mounting the reflection preventing member withrespect to the case.

With such a structure, it is possible to facilitate the assembling ofthe image read/write head.

Preferably, the reflection preventing member may include an upper wallfacing but spaced from the plurality of light receiving elements and theplurality of drive ICs thicknesswise of the substrate. The upper wallmay includes a slit for allowing light traveling through the pluralityof lenses to reach the plurality of light receiving elements. Thereflection preventing member may also include a plurality of elasticallydeformable side walls projecting from the upper wall toward thesubstrate into contact therewith.

With such a structure, the light receiving elements and the drive ICscan be appropriately surrounded by the upper wall and the sidewalls.Since the sidewalls are elastically deformed into contact with thesubstrate, it is unlikely that gaps are defined between the side wallsand the substrate. Therefore, it is possible to reliably preventexternal light from entering the region surrounded by the reflectionpreventing member.

Preferably, the substrate may be black at least at portions in contactwith the plurality of side walls.

With such a structure, even if such gaps are formed, most of the lightprogressing through the gaps can be absorbed by the black portions ofthe substrate. This further reliably prevents the external light fromentering the region surrounded by the reflection preventing member.

Preferably, the light source may be mounted beside the plurality oflight receiving elements on the surface of the substrate on which theplurality of light receiving elements are mounted. The reflectionpreventing member may include a side wall for separating the lightsource from the plurality of light receiving elements.

With such a structure, since all of the light receiving elements, theprinting elements, the drive ICs and the light source are mounted on thesame surface of the substrate, the production efficiency of the imageread/write head can be enhanced. The reflection preventing memberappropriately prevents the light emitted from the light sources fromdirectly reaching the light receiving elements.

In accordance with a fourth aspect of the present invention, there isprovided an image read/write head comprising a substrate which carries aplurality of light receiving elements, a plurality of printing elementsand a plurality of drive IC chips incorporating driving circuits forproviding drive control of the printing elements, a case mounted on thesubstrate for surrounding the plurality of light receiving elementswhile avoiding the plurality of printing elements, a transparent covermounted to the case for contact with a document being transferred, alight source disposed in the case for illuminating the document, and aplurality of lenses disposed in the case for forming, on the pluralityof light receiving elements, an image of the document illuminated by thelight source. The image read/write head further includes detecting meansfor detecting at least one of the document fed onto the transparentcover and a recording paper fed to a position facing the plurality ofprinting elements.

With the image read/write head having such a structure, the imageread/write head itself is provided with means for detecting the documentor the recording paper. Therefore, it is possible to eliminate thenecessity for providing detecting means for the document or therecording paper separately from the image read/write head, or to reducethe number of such separate detecting means. Further, it is possible toeasily and precisely position the detecting means relative to respectiveparts of the image read/write head. Therefore, it is possible to reducethe cost for manufacturing an image processing apparatus utilizing theimage read/write head.

Preferably, the detecting means may include a movable member having oneend for contacting the document in a document transfer path. The movablemember has another end for facing the light source. The movable memberis so arranged that said another end blocks light traveling from thelight source toward the transparent cover when said one end is out ofcontact with the document, whereas said another end retreats to aposition which does not block the light when said one end is in contactwith the document.

With such a structure, the presence or absence of the document can bedetermined by utilizing the light source or the light receiving elementsincorporated in the image read/write head. Specifically, when thedocument is not fed toward the transparent cover and hence is not incontact with the one end of the movable member, the light traveling fromthe light source toward the transparent cover is blocked by the anotherend of the movable member. In this case, therefore, the light receivingelements do not receive the light emitted from the light source. On theother hand, when the document is fed toward the transparent cover and isin contact with the one end of the movable member, the another endretreats to a position which does not block the light emitted from thelight source. In this case, therefore, the light emitted from the lightsource is reflected by the document on the transparent cover to bereceived by the light receiving elements. In this way, the presence orabsence of the document can be determined by whether or not the lightreceiving elements receive the light. With the above-describedstructure, the presence of absence of the document can be determined byeffectively utilizing the parts originally incorporated in the imageread/write head. Such a structure is reasonable and allows the detectingmeans to be provided at a low cost.

Preferably, the detecting means may include a movable member having oneend for contacting the document in the document transfer path. Themovable member has another end arranged in a light path extending fromthe transparent cover to the plurality of light receiving elements. Themovable member is so arranged that said another end blocks lighttraveling from the transparent cover toward the plurality of lightreceiving elements when said one end is out of contact with thedocument, whereas said another end retreats to a position which does notblock the light when said one end is in contact with the document.

With such a structure, when the document is not fed toward thetransparent cover and hence is not in contact with the one end of themovable member, the another end of the movable member blocks the lighttraveling from the transparent cover toward the light receivingelements. In this case, therefore, the light receiving elements do notreceive the light emitted from the light source. On the other hand, whenthe document is fed toward the transparent cover and is in contact withthe one end of the movable member, the another end retreats to aposition which does not block the light reflected by the surface of thedocument. In this case, therefore, the light is received by the lightreceiving elements. In this way, also with this structure, the presenceor absence of the document can be determined by effectively utilizingthe parts originally incorporated in the image read/write head.

Preferably, the detecting means may include a movable member having oneend for contacting the recording paper in a recording paper transferpath. The movable member has another end arranged in a light pathextending from the transparent cover to the plurality of light receivingelements. The movable member is so arranged that said another end movesbetween a position for blocking light traveling from the transparentcover toward the plurality of light receiving elements and a positionwhich does not block the light depending on whether or not said one endis in contact with the recording paper.

With such a structure, in accordance with the presence or absence of therecording paper at a predetermined position, the light receivingelements shift between a state capable of receiving the light travelingfrom the transparent cover and a state incapable of receiving suchlight. Therefore, the presence or absence of the recording paper at thepredetermined position can be determined by whether or not the lightreceiving elements are in a state capable of receiving light. Thus, withthe above-described structure, the presence or absence of the recordingpaper can be determined by effectively utilizing the parts originallyincorporated in the image read/write head, which is reasonable.

In accordance with a fifth aspect of the present invention, there isprovided an image read/write head comprising a substrate which carries aplurality of light receiving elements, a plurality of printing elementsand a plurality of drive IC chips incorporating driving circuits forproviding drive control of the printing elements, a case mounted on thesubstrate for surrounding the plurality of light receiving elements butavoiding the plurality of printing elements, a transparent cover mountedto the case for contact with a document being transferred, a lightsource disposed in the case for illuminating the document and aplurality of lenses disposed in the case for forming, on the pluralityof light receiving elements, an image of the document illuminated by thelight source. The plurality of light receiving elements, the pluralityof printing elements and the plurality of drive IC chips are mounted ona same surface of the substrate. The image read/write head furtherincludes supporting means for supporting a platen roller disposed infacing relationship to at least either one of the transparent cover andthe plurality of printing elements, a reflection preventing memberprovided separately from the case for collectively surrounding theplurality of light receiving elements and the plurality of drive ICchips and detecting means for detecting at least one of the document fedonto the transparent cover and a recording paper fed to a positionfacing the plurality of printing elements.

With the image read/write head having such a structure, it is possibleto obtain the same advantages as those of the image read/write headprovided in accordance with each of the first, the third and the fourthaspects of the present invention.

In accordance with a sixth aspect of the present invention, there isprovided an image read head comprising a substrate which carries aplurality of light receiving elements, a case mounted on the substratefor surrounding the plurality of light receiving elements, a transparentcover mounted to the case for contact with a document being transferred,a light source disposed in the case for illuminating the document and aplurality of lenses disposed in the case for forming, on the pluralityof light receiving elements, an image of the document illuminated by thelight source. The image read/write head further includes detecting meansfor detecting the document fed onto the transparent cover.

With the image read/write head having such a structure, it is possibleto eliminate or lessen the necessity for separately providing means fordetecting the document. Further, it is possible to easily and preciselyposition the detecting means relative to respective parts of the imageread/write head. Therefore, it is possible to reduce the cost formanufacturing an image processing apparatus utilizing the imageread/write head.

In accordance with a seventh aspect of the present invention, there isprovided a printhead including a substrate carrying a plurality ofprinting elements. The printhead includes detecting means for detectinga recording paper fed to a position facing the plurality of printingelements.

With the printhead having such a structure, it is possible to eliminateor lessen the necessity for separately providing means for detecting therecording paper. Further, it is possible to easily and preciselyposition the detecting means relative to the respective parts of theprinthead. Therefore, it is possible to reduce the cost formanufacturing a printer utilizing the printhead.

Other features and advantages of the present invention will becomeclearer from the detailed description of preferred embodiments givenbelow with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an example of image read/write headin accordance with the present invention.

FIG. 2 is an exploded perspective view of the image read/write headshown in FIG. 1.

FIG. 3 is a sectional view taken along lines III—III in FIG. 1.

FIG. 4 is a sectional view taken along lines IV—IV in FIG. 1 showing theprincipal portion.

FIG. 5 is a sectional view taken along lines V—V in FIG. 4.

FIG. 6 schematically illustrates the structure of an image processingapparatus incorporating the image read/write head shown in FIG. 1.

FIG. 7 is a perspective view showing another example of image read/writehead in accordance with the present invention.

FIG. 8 is a perspective view showing the principal portion of anotherexample of image read/write head in accordance with the presentinvention.

FIG. 9 is a sectional view showing another example of image read/writehead in accordance with the present invention.

FIG. 10 is a sectional view showing another example of image read/writehead in accordance with the present invention.

FIG. 11 is a sectional view showing another example of image read/writehead in accordance with the present invention.

FIG. 12 is a sectional view showing an example of image read head inaccordance with the present invention.

FIG. 13 is a sectional view showing an example of printhead inaccordance with the present invention.

FIG. 14 is a perspective view showing another example of componentsmounted on the substrate of an image read/write head in accordance withthe present invention.

FIG. 15 is a sectional view showing a prior art structure.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present invention will be described belowwith reference to the accompanying drawings.

FIGS. 1 through 5 illustrate an example of image read/write headaccording to the present invention.

As clearly shown in FIGS. 1 through 3, the image read/write head Acomprises a case 1, a plurality of sensors 2A for detecting a document,a plurality of sensors 2B for detecting a recording paper, a transparentcover 19, a lens array 5, a reflection preventing member 6, a substrate4, a heat sink plate 47 and other parts which will be described later.

The substrate 4, which may be made of a ceramic material for example, isin the form of an elongated rectangular plate. The substrate 4 has anobverse surface (upper surface) 4 a which is provided with a pluralityof light sources 30, a plurality of light receiving elements 3, aplurality of drive IC chips 80 and a plurality of heating elements 8.

The light sources 30, each of which may comprise an LED chip, arearranged on the substrate 4 at a predetermined pitch in a row extendinglongitudinally of the substrate. The light receiving elements 3 forperforming photo-electric conversion are integrally built in sensor ICchips 3A which are rectangular semiconductor chips. The sensor IC chips3A are mounted in a row on the substrate 4 in such a manner that the rowof light receiving elements 3 extends substantially in parallel to therow of light sources 30. The heating elements 8, which are an example ofprinting elements in the claimed invention, are arranged similarly tothat used in a conventional thermal printhead. Specifically, the heatingelements 8 may be provided by printing and baking a thick film ofresistor paste containing, for example, ruthenium oxide as a conductivesubstance into a line extending longitudinally of the substrate 4, andthen providing a wiring pattern to electrically divide the resistor lineat a predetermined pitch longitudinally thereof. The drive IC chips 80incorporate driving circuits for controlling the heating operation ofthe heating elements 8. Similarly to the light sources 30, the drive ICchips are arranged at a predetermined pitch in a row extendinglongitudinally of the substrate 4.

The row of heating elements 8 is disposed on the substrate 4 at oradjacent one longitudinal edge 4 c of the substrate 4. On the otherhand, the rows of drive IC chips 80, light receiving elements 3 andlight sources 30, respectively, are disposed at a portion which iscloser to the other end edge 4 d of the substrate 4 than the row ofheating elements 8. The obverse surface 4 a of the substrate 4 is formedwith a wiring pattern (not shown) connected to the above-describedcomponents mounted on the obverse surface 4 a. The substrate 4 is alsoprovided, at appropriate portions, with one or plural connectors (notshown) which are electrically connected to the wiring pattern. Byconnecting an external device to the connector, it is possible toperform power supply and input/output of various signals with respect tothe above-described components.

The heat sink plate 47 is provided for allowing heat generated at theheating elements 8 to dissipate to the outside. The heat sink plate maybe made of a metal having a high heat conductivity. The heat sink plate47 may comprise a plate which is substantially identical in size andconfiguration to the substrate 4. The heat sink plate may be bonded tothe reverse surface 4 b of the substrate 4 with a bonding tape or anadhesive.

The case 1, which may be made of a white synthetic resin, has anelongated configuration. The case 1 is integrally formed, atlongitudinally opposite ends thereof, with a pair of supports 7 forsupporting a platen roller P₂ for a recording paper. Each of thesupports 7 projects laterally outward from an outer side surface 1 a ofthe case 1, and has an upper portion formed with an upwardly open recess70 for fitting a shaft portion of the platen roller P₂. The case 1 ismounted on the substrate 4 and the heat sink plate 47 in such a manneras to avoid the heating elements 8 and its adjacent portion but to coverother portions on the obverse surface 4 a of the substrate 4. Thesubstrate 4 projects laterally outwardly from the case 1 at a portion onwhich the heating elements 8 are mounted. The recess 70 of each support7 is located on an extension line of the row of heating elements 8. Eachof the supports 7 is formed with a respective one of paired projections71 at a lower portion thereof, and the longitudinally opposite ends ofthe heat sink plate 47 are disposed on the pair of projections 71. Thus,the case 1, the substrate 4 and the heat sink plate 47 are stablycombined with each other.

The transparent cover 19 is provided for guiding a document D thereon.The transparent cover is formed of a glass material or synthetic resinhaving a high transparency. The case 1 is formed, at the upper surfacethereof, with a recess 13 into which the transparent cover 19 is fittedin facing relationship to the obverse surface 4 a of the substrate 4 asspaced away therefrom. The upper surface of the case 1 and the recess 13are inclined so that the transparent cover 19 is inclinedcorrespondingly. Specifically, the transparent cover 19 is so inclinedas to become lower as it extends farther from the edge 4 c of thesubstrate 4. The outer side surface 1 a of the case 1 is so inclined asto become farther from the edge 4 c of the substrate 4 as it extendsupwardly.

The lens array 5 comprises a plurality of lenses 51 arranged in a rowand held in an elongated lens holder 50 formed of a synthetic resin. Forthe lens 51, use may be made of a selfoc lens capable of forming anon-inverted, non-magnified image of the document D on each of the lightreceiving elements 3. However, the present invention is not limitedthereto, and other lenses may be employed for the present invention. Thelens array 5 is fitted into a groove 12 formed in the case 1 and therebybuilt in the case 1 below and in facing relationship to the transparentcover 19. A linear portion of the obverse surface of the transparentcover 19 positionally corresponding to the lenses 51 serves as an imagereading line S.

The case 1 internally defines a first light path 14 a and a second lightpath 14 b for guiding light emitted from the light sources 30. The firstlight path 14 a, which extends over the height of the case 1, functionsto guide light emitted from the light sources 30 to the image readingline S. The second light path 14 b, which includes the groove 12,functions to guide the light reflected on the image reading line S tothe light receiving elements 3 via the lenses 51. Since the case 1 ismade of white synthetic resin as described before, the light emittedfrom the light sources 30 is guided to the image reading line S whilebeing repetitively reflected on the white wall surfaces of the firstlight path 14 a at a high reflectivity. Therefore, it is possible toefficiently illuminate the image reading line S.

The reflection preventing member 6 may be made of polycarbonate or ABSresin containing a black pigment or glass powder, for example. Thereflection preventing member 6 has a black surface to provide high lightabsorption. The reflection preventing member 6 is disposed in a recess11 formed at the bottom of the case 1 in such a manner as to surroundthe sensor IC chips 3A including the light receiving elements 3, and thedrive IC chips 80. Specifically, the reflection preventing member 6comprises an upper wall 60 located above the sensor IC chips 3A and thedrive IC chips 80 and extending longitudinally of the case 1, and sidewalls 61 a, 61 b respectively projecting downward from widthwiseopposite edges of the upper wall 60, and two side walls 61 c, 61 drespectively projecting downward from longitudinally opposite ends ofthe upper wall 60, as clearly shown in FIG. 2. These side walls 61 a˜61d surround the light receiving elements 3 and the drive ICs 80 on foursides. The reflection preventing member 6 originally has a height whichis slightly greater than the height of the recess 11, so that thereflection preventing member is fitted into the recess 11 as compressedin the thickness direction. Therefore, each of the four side walls 61a˜61 d is elastically deformed appropriately to come into contact withthe obverse surface 4 a of the substrate 4 at the tip end thereof. Theupper wall 60 is formed with a slit 63 for preventing the second lightpath 14 b from being blocked.

The obverse surface 4 a of the substrate 4 includes a black coatingregion (indicated by a reference sign N1 in FIG. 3) at portions whichare in contact with the respective tip ends of the side walls 61 a˜61 d.The black coating region is provided with a black glass layer formed byapplying a glass paste containing a black pigment and then baking thesame. Alternatively, the black coating region may be formed by applyinga coating containing a Fe—Cr—Co-based or a Cu—Cr-based black pigment ora black pigment of another composition having a high light shieldingability. In the present invention, in addition to the above-describedregion, the black coating may be applied to the entire region of theobverse surface 4 a of the substrate 4 surrounded by the reflectionpreventing member 6 and additionally to an excess region extendingbeyond the surrounded region.

As clearly shown in FIG. 4, the upper wall 60 of the reflectionpreventing member 6 is formed with a plurality of projections 64 whichare inserted into a plurality of recesses 15 provided in the case 1. Thereflection preventing member 6 is thus mounted to the case 1. Thereflection preventing member 6 is formed, at one of widthwise oppositeedges thereof, with a plurality of clamping projections 65 each having agroove 65 a. As clearly shown in FIG. 5, the case 1 is formed with ribs16 arranged in the first light path 14 a each of which is elasticallyclamped by the corresponding clamping projection 65 in its thicknessdirection. The reflection preventing member 6 is mounted to the case 1by the clamping function of the clamping projections 65 for preventingthe reflection preventing member from deviating longitudinally orwidthwise relative to the case 1. The plural ribs 16 are arranged at apredetermined pitch longitudinally of the first light path 14 a forenhancing the rigidity of the case 1.

As clearly shown in FIG. 3, the upper surface of the case 1 is formedwith a plurality of recesses 17 a into which the sensors 2A are fitted,so that the sensors are incorporated adjacent the transparent cover 19.Each of the sensors 2A is provided with a lever 20 a projecting upwardrelative to the upper surface of the case 1 in its normal state (i.e.when the document is not fed onto the transparent cover 19). When thelever 20 a is pressed downward upon contacting the document D, thesensor outputs a predetermined detection signal. Each of the recesses 17a communicates with a hole 17 a′ provided below the recess 17 a. Aconnection cord 21 a for the sensor 2A extends downward through the hole17 a′ to the outside of the case 1. As clearly shown in FIGS. 1 and 2,the sensors 2A are arranged at predetermined intervals longitudinally ofthe case 1 for detecting the width of the document D to be transferredto the transparent cover 19.

The sensors 2B are fitted into a plurality of recesses 17 b formed inthe outer side surface 1 a of the case 1, and are thus built in the case1. Each of the sensors 2B is provided with a lever 20 b which is sobiased as to project laterally outwardly from the outer side surface 1 aof the case 1. The lever 20 b is movable between an outwardly projectingposition and an inwardly retreating position with respect to the outerside surface 1 a depending on whether it is in contact with therecording paper K. When the lever 20 b is in the projecting positionwithout being depressed by the recording paper K, the sensor 2B outputsa predetermined detection signal for notifying the paper-out conditionof the recording paper K. The case 1 is further formed with a groove 17b′ extending longitudinally of the case below the recesses 17 b incommunication therewith. A connection cord 21 b for each sensor 2Bextends laterally through the groove 17 b to the outside of the case 1through each longitudinal end of the case 1 while being supported (notshown) by the reflection preventing member 6. The number of the sensors2B may be two for example, and these two sensors 2B may be arranged at apredetermined pitch longitudinally of the case 1. This is because, therecording paper paid out from a roll of an elongated paper has aconstant width, so that, unlike the document, width variations need notbe considered. From this point of view, only one sensor 2B may beprovided for detecting the recording paper. Similarly, when the width ofthe document need not be considered, only one sensor 2A may be providedfor detecting the document.

FIG. 6 illustrates an image processing apparatus B incorporating theabove-described image read/write head A.

The image processing apparatus includes a housing 9 made of syntheticresin for accommodating the image read/write head A, and a pair ofplaten rollers P₁, and P₂ for the document and the recording paper,respectively.

The platen roller P₁ has shaft portions 90 a provided at longitudinallyopposite ends thereof. The housing 9 is provided with brackets 91 a forcarrying the shaft portions 90 a of the platen roller P₁ so that theroller body of the platen roller can face the surface of the transparentcover 19. The platen roller P₁, is driven to rotate for transferring thedocument D which is fed via an insertion port 92 a provided in thehousing 9 and guided between the platen roller P₁ and the transparentcover 19 toward a discharge port 92 b of the housing 9 in close contactwith the transparent cover 19. When the document D is being fed to thetransparent cover 19, the document D passes over the sensors 2A.

The platen roller P₂ has shaft portions 90 b provided at thelongitudinally opposite ends. The shaft portions 90 b are respectivelyfitted into the recesses 70 of the supports 7. As a result, the rollerbody of the platen roller P₂ is arranged in facing relationship to theheating elements 8. The shaft portions 90 b are also supported bybrackets 91 b separately provided in the housing 9. The housing 9 alsoaccommodates a roll R formed by winding an elongated thermosensitiverecording paper K. The platen roller P₂ is driven to rotate fortransferring the recording paper K which is paid out from the roll R andguided between the platen roller P₂ and the heating elements 8 toward adischarge port 92 b. Before reaching the discharge port 92 b, therecording paper K passes over the sensors 2B provided in the outer sidesurface 1 a of the case 1.

The image read/write head A is pivotally movable up and down about theshaft portions 90 b, as indicated by an arrow Na. Specifically, theshaft portions 90 b of the platen roller P₂ are held at predeterminedpositions by the brackets 91 b. On the other hand, the supports 7 of theimage read/write head A are fitted slidably on the shaft portions 90 bfor circumferential movement. Thus, the shaft portions 90 b serve as apivotal axis of the image read/write head A. Below the heat sink plate47, a spring 94 is provided in engagement with the reverse surface ofthe heat sink plate 47 for pushing the image read/write head A upward.The spring 94 is arranged at a portion which is offset, widthwise of thesubstrate 4 or the heat sink plate 47, from the center 0 of the shaftportions 90 toward the transparent cover 19 by an appropriate distanceL. With the pushing force F of the spring 94, the image read/write headA is biased pivotally upward so that the surface of the transparentcover 19 is pressed against the platen roller P₁.

The image processing apparatus B incorporates a main controller 93including various memories and a CPU for example. Based on apredetermined program or the functions of operation switches (not shown)provided in the image processing apparatus B, the main controller 93controls the rotation of the paired platen rollers P₁, P₂, processes theimage signals obtained in the image read/write head A and transmits theprinting image data to the image read/write head A for input to thedrive IC chips 80 while performing other operation control and dataprocessing. The signals output from the sensors 2A, 2B are alsotransmitted to the main controller 93.

Next, the operation of the above-described image read/write head A andthe image processing apparatus B will be described.

For reading an image of the document D, when the document D fed throughthe insertion port 92 a into the housing 9 is guided onto the uppersurface of the case 1, the levers 20 a of the sensors 2A are depressedby the document D. Accordingly, the sensors 2A notify the presence ofthe document by transmitting signals to the main controller 93. As aresult, the platen roller P₁, the light sources 30 and the lightreceiving elements 3 are driven under the control of the controller 93.When reading for one sheet of the document D has almost finished and thetrailing edge of the document D has already passed over the levers 20 a,each of the levers 20 a returns to its original posture and projectsupwardly from the upper surface of the case 1. At this time, theabove-described signal output from the sensors 2A stops. The imagereading of the document D by the image read/write head A is continuedfor a certain period of time after the termination of the signal output,and is then interrupted until another document D is newly set.

Image reading of the document D is performed by illuminating the surfaceof the document D with light emitted from the light sources 30 andreceiving the reflected light by the light receiving elements 3 via thelenses 51. Since the light receiving elements 3 are surrounded by theblack reflection preventing member 6 having high light absorbingability, the light traveling from the document D toward the lightreceiving elements are prevented from being reflected around the lightreceiving elements 3.

The reflection preventing member 6 also prevents the light from outsidethe case 1 from reaching the light receiving elements 3, or the lightemitted from the light sources 30 from directly traveling toward thelight receiving elements 3. Particularly, the side walls 61 a˜61 d ofthe reflection preventing member 6 are compressed into contact with theobverse surface 4 a of the substrate 4, thereby reducing the likelihoodof forming light entering gaps between these members. Further, even ifsuch gaps are formed, the black coating of the substrate 4 provided atportions held in contact with the respective tip ends of the side walls61 a˜61 d absorbs most of the light progressing through the gaps. Thisfurther reliably prevents the light from the outside of the case 1 orthe light emitted from the light sources 3 and traveling toward thelight receiving elements 2 from disadvantageously entering the regionsurrounded by the reflection preventing member 6. As a result, it ispossible to prevent the light receiving elements 3 from receivingundesirable light which may cause noises, so that a read image having ahigh image quality can be provided.

For subsequently printing the image on the recording paper K, theprinting image data are transmitted from the main controller 93 to thedrive ICs 80, which makes the heating elements 8 to be selectivelyheated. When the recording paper K is appropriately set, the levers 20 bof the sensors 2B are depressed by the recording paper K. When therecording paper K runs out, the levers 20 b projects outward from theouter side surface 1 a of the case 1. At this time, the sensors 2Boutput signals to notify the paper-out condition. In this case, theimage printing is interrupted, and a paper-out message may be displayedon a display portion (not shown) provided in the image processingapparatus B for example.

The image read/write head A includes the sensors 2A, 2B of its own fordetecting a document and a recording paper, respectively. Therefore, inassembling the image processing apparatus B, it is not necessary tomount these sensors 2A, 2B separately from the image read/write head Ain the housing 9. Moreover, in mounting the image read/write head A inthe housing 9, troublesome positioning of the sensors 2A, 2B is notnecessary, because the sensors are appropriately positioned at thepredetermined portions of the image read/write head A. Therefore, it ispossible to easily assemble the image processing apparatus B.

The platen roller P₂ and the image read/write head A can be positionedrelative to each other by fitting the shaft portions 90 b onto thesupports 7. Therefore, the image read/write head A and the platen rollerP₂ can be easily mounted in the housing 9 as appropriately positionedrelative to each other. On the other hand, the image read/write head Ais pivotally movable about the shaft portions 90 b, and the transparentcover 19 is pressed against the platen roller P₁ by the elastic force Fof the spring 94. Therefore, positioning of the platen roller P₁,relative to the image read/write head A is also easily performed.Moreover, the pivotal movement of the image read/write head A about theshaft portions 90 b allows the distance between the platen roller P₁,and the transparent cover 19 to follow the thickness of the document D.Therefore, it is possible to transfer documents of various thicknessessmoothly in close contact with the surface of the transparent cover 19while also preventing the jam of documents D.

In the image processing apparatus B, both of the paired platen rollersP₁, P₂ are arranged above the transparent cover 19 or the substrate 4.Therefore, the three members, i.e., the paired platen rollers P₁, P₂ andthe image read/write head A are prevented from becoming bulky in theheight direction of the image processing apparatus B, which leads to athickness reduction of the image processing apparatus B.

In the image read/write head A, all of the light sources 30, the sensorIC chips 3A incorporating the light receiving elements 3, the drive ICchips 80, and the heating elements 8 are mounted on the obverse surface4A of the substrate 4. Accordingly, the wiring pattern for thesecomponents is also provided on the obverse surface 4 a of the substrate4. Therefore, mounting of these components and forming of the wiringpattern can be performed without turning over the substrate 4, whichenhances the productivity.

The reflection preventing member 6 collectively surrounds the sensor ICchips 3A incorporating the light receiving elements 3, and the drive ICchips 80. Specifically, the reflection preventing member 6 does notinclude a wall for partitioning the sensor IC chips 3A and the drive ICchips 80. Therefore, even when the distance between the row of IC chips3A and the row of IC chips 80 is small, it is possible to prevent thereflection preventing member 6 from undesirably contacting these ICchips 3A, 80 or the wires bonded thereto. This also enhances theproductivity of the image read/write head A.

In the image processing apparatus B, image reading of the document D andimage printing on the recording paper K may be simultaneously performed.Since the outer side surface 1 a of the case 1 is so inclined as tobecome farther from the platen roller P₂ as it extends upward, thetransparent cover 19 can be positioned away from the platen roller P₂.Further, the transparent cover 19 is so inclined that its obversesurface is oriented away from the platen roller P₂, the platen roller P₁which faces the transparent cover 19 can be positioned away from theplaten roller P₂. Therefore, it is possible to keep a relatively longdistance between the paired platen rollers P₁ and P₂ while alsopreventing the image read/write head A from becoming large. Thisstructure is advantageous in preventing the document transfer path andthe recording paper transfer path provided by the paired platen rollersP₁, and P₂, respectively; from interfering with each other.

FIGS. 7–14 illustrate another example of the present invention. In thisfigures, the elements which are identical or similar to those of theabove-described embodiment are designated by the same reference signs asthose used for the above-described embodiment.

In the image read/write head Aa shown in FIG. 7, a pair of supports 7Afor supporting a platen roller P₂ are provided utilizing a heat sinkplate 47A. Specifically, the pair of supports 7A are formed by raisingthe longitudinally opposite ends of the heat sink plate 47A, whichcomprises a metal plate and is disposed on the reverse surface of asubstrate 4, to flank the longitudinally opposite ends of the substrate4. Similarly to the supports 7 in the above-described embodiment, eachof the supports 7A is formed with a recess 70 for fitting thecorresponding shaft portion 90 b of the platen roller P₂.

With the image read/write head Aa, the platen roller P₂ can be supportedby the supports 7A, similarly to the image read/write head A in theabove-described embodiment. Further, it is possible to easily positionthe platen roller P₂ relative to the heating elements 8.

In this image read/write head Aa, the longitudinally opposite ends ofthe heat sink plate 47A are integrally formed with a pair of engagingprojections 74, which are brought into engagement with a pair ofrecesses 18 formed at the longitudinally opposite ends of the case 1.With this structure, it is possible to easily assemble the case 1 withthe heat sink plate 47 and the substrate 4. Assembling of the case 1 canbe enhanced by another means. For example, the case 1 may be integrallyformed with engaging projections 74 a for engagement with the reversesurface of the heat sink plate 47A, as shown in FIG. 8.

In the present invention, as is clear from the structure shown in FIG.7, the supporting means for supporting the platen roller may be providedat the heat sink plate, or the substrate or any other memberconstituting the image read/write, instead of providing at the case.Moreover, instead of providing a supporting means for supporting therecording paper platen roller, a supporting means for supporting thedocument platen roller may be provided. Alternatively, the imageread/write head in accordance with the present invention may be providedwith two supporting means for supporting the recording paper platenroller and the document platen roller, respectively.

The platen roller may be supported by the supporting means in variousmanners, and the supporting manner is not limitative on the presentinvention. For example, in the present invention, the platen roller P₂may be supported only by the supports 7 without using the brackets 91 bshown in FIG. 6. Further, instead of the generally semicircular recess70, the supporting means in the present invention may be formed with arecess of another configuration, or a non-cutout hole for insertingtherethrough the shaft portion of the platen roller.

FIG. 9 illustrates an image read/write head Ab which includes a movablemember 24 provided in a hollow portion 23 a of a case 1A. The movablemember 24, which is L-shaped in section, has an intermediate portionpivotally supported on a shaft 25 a. One end 24 a of the movable memberis movable to project outward and retreat inward relative to the uppersurface of the case 1A which provides the transfer path for the documentD. The movable member 24 is normally biased by an elastic member (notshown) in a predetermined direction so that the end 24 a projects upwardrelative to the upper surface. When the document D is fed onto the uppersurface of the case 1A, the end 24 a is pressed downward as indicated bysolid lines in the figure, causing the entirety of the movable member 24to pivot about the shaft 25 a. The other end 24 b of the movable member24 is arranged within a first transfer path 14 a. When the end 24 aprojects upward relative to the upper surface of he case 1A, the otherend 24 b is so positioned as to block the light emitted from the lightsources 30, as indicated by phantom lines in the figure. On the otherhand, when the end 24 a is pressed downward by the document D, the otherend 24 b moves to a position which does not block the light emitted fromthe light sources, as indicated by solid lines in the figure.

In the image read/write head Ab having the above-described structure,the light emitted from the light sources is blocked by the end 24 b ofthe movable member 24 when the document D is not set on the uppersurface of the case 1A. Therefore, the light emitted from the lightsources 30 does not reach the transparent cover 19, and hence, is notreceived by the light receiving elements 3. On the other hand, when thedocument D is set on the upper surface of the case 1A and thetransparent cover 19, the end 24 a of the movable member 24 is presseddownward by the document D so that the other end 24 b correspondinglymoves to a position which does not block the light emitted from thelight sources 30. Therefore, the light emitted from the light source 30reaches the surface of the document on the transparent cover 19 and isreflected thereon to be received by the light receiving elements 3.Therefore, whether or not the document D is set on the transparent cover19 can be appropriately determined by whether or not the light receivingelements 3 are in a state capable of receiving light. Such a documentdetecting means can be provided at a low cost by effectively utilizingthe light receiving elements 3 and the light sources 30 incorporated inthe image read/write head.

In the image read/write head Ab having the above-described structure,all of the light receiving elements 3 and the light sources 30 need notbe utilized for determining the presence or absence of the document.That is, the presence or absence of the document can be determined byutilizing part of the light receiving elements and part of the lightsources. With such a structure, it is only necessary that the end 24 bof the movable member 24 has a size sufficient for blocking the lightemitted from a selected one or ones of the light sources 30, so that thesize of the movable member 24 can be correspondingly reduced. This istrue with respect to image read/write heads Ac, Ad which will bedescribed later.

FIG. 10 illustrates an image read/write head Ac which includes a movablemember 26 provided in a hollow portion 23 b formed at an upper portionof a case 1B. The movable member 26, which is L-shaped in section, hasan intermediate portion pivotally supported on a shaft 25 b. One end 26a of the movable member 26 is movable to project outward and retreatinward relative to the upper surface of the case 1B which provides thetransfer path for the document D. The movable member 26 is normallybiased by an elastic member (not shown) in a predetermined direction sothat the end 26 a projects upward relative to the upper surface. Whenthe document D is present on the upper surface of the case 1B, the end26 a is pressed downward as indicated by solid lines in the figure,causing the entirety of the movable member 26 to pivot about the shaft25 b. The other end 26 b of the movable member 26 is arranged within asecond transfer path 14 b. When the end 26 a projects upward relative tothe upper surface of the case 1B, the other end is positioned in facingrelationship to a lens 51, thereby preventing light from entering thelens 51. On the other hand, when the end 26 a is pressed downward by thedocument D, the other end 26 b moves to a position which does not facethe lens 51, thereby allowing light from the image reading line S toenter the lens 51.

In the image read/write head Ac having the above-described structure,when the document D is not present on the upper surface of the case 1Band hence the end 26 a of the movable member 26 is not depressed by thedocument D, the lens 51 is covered with the other end 26 b. Therefore,the light receiving elements 3 cannot receive light. On the other hand,when the document D is present on the upper surface of the case 1B andthe transparent cover 19 to press the end 26 a of the movable member 26downward, the other end 26 b moves to a position which does not face thelens 51. Therefore, the light emitted from the light source 30 andreflected on the surface of the document D progresses through the lens51 to be received by the light receiving elements 3. Thus, also in thisimage read/write head Ac, similarly to the above-described imageread/write head Ab, whether or not the document D is present at apredetermined position can be appropriately determined by whether or notthe light receiving elements 3 are in a state capable of receivinglight. Thus, the light receiving elements 3 and the light sources 30 canbe effectively utilized for detecting the document.

FIG. 11 illustrates an image read/write head Ad which includes a case 1Cformed with a slit-shaped hollow portion 23 c extending from an outerside surface 1 a to a second light transfer path 14 b. A movable member27 is provided in the hollow portion 23 c. The movable member 27 isslidable in the hollow portion 23 c in the directions indicated by anarrow Nd, and has one end 27 a which is movable to project outward andretreat inward relative to the outer side surface 1 a of the case 1Cwhich serves as a transfer path for the recording paper K. The movablemember 27 has a spring portion 27 c having an elastic force for normallyforcing the end 27 a to project outward from the outer side surface 1 a.When the recording paper K is in contact with the outer side surface 1a, the movable member 27 moves against the elastic force so that the end27 a retreats into the case 1C. The other end 27 b of the movable member27 retreats in the hollow portion 23 c so as not to block the secondlight transfer path 14 b below lenses 51 when the end 27 a projectsoutward from the outer side surface 1 a. On the other hand, when the end27 a retreats into the case 1C, the other end 27 b projects from thehollow portion 23 c into the second light transfer path 14 b.

With the image read/write head Ad having the above-described structure,in accordance with the presence or absence of the recording paper K onthe outer side surface 1 a of the case 1C, the second light transferpath 14 b shifts between a blocked state and a non-blocked statedepending on the movement of the end 27 b of the movable member 27.Therefore, whether or not the recording paper K is present at apredetermined position can be appropriately determined based on whetheror not the light receiving elements 3 are in a state capable ofreceiving light emitted from the light sources 30 and reflected by thedocument D or the platen roller P₁. However, with the above-describedstructure, the image reading operation of the document cannot beperformed when the second light transfer path 14 b is blocked by the end27 b. Therefore, the image read/write head Ad may be preferably usedwhere image reading of the document and printing on the recording paperare not simultaneously carried out. Moreover, since the image readingoperation cannot be performed while the recording paper K is pressingthe end 27 a of the movable member 27, cut sheets of recording paper maybe preferably used for the image read/write head Ad for avoiding thecondition in which the end 27 a of the movable member 27 is alwayspressed by the recording paper.

The specific structure of the detecting means for the document and therecording paper is not limited in the present invention to those of theabove-described embodiments. In the present invention, a sensor or aswitch structured differently from those of the above-describedembodiments may be employed for detecting the document and the recordingpaper. As a detecting means, a reflective type photointerrupter oranother optical sensor may be employed for detecting the document andthe recording paper in a non-contacting manner. Further, the positionand the number of the detecting means in the above-described embodimentsare not limitative.

Although an image read/write head is exemplarily described in theabove-described embodiments, the present invention is not limitedthereto. For example, as shown in FIG. 12, the present invention isapplicable to an image read head which includes a case 1D, a transparentcover 19, a lens array 5, a plurality of light receiving elements 3 anda plurality of light sources 30, but which does not include printingelements. In this image read head, the case 1D is provided with adetecting means 2D for a document. With such a structure, mounting ofthe detecting means can be performed more easily than mounting thedetecting means separately from the image reading head.

The present invention is also applicable to a printhead which has thesole function of printing on a recording paper. The printhead shown inFIG. 13 includes a substrate 4A on which are mounted a plurality ofheating elements 8 and a plurality of drive IC chips 80 for providingdrive control of the heating elements 8. The substrate 4A is formed witha recess 48 which receives a sensor 2E for detecting a recording paper.The printhead having such a structure is included in the scope of thepresent invention.

FIG. 14 illustrates the parts mounted on a substrate 4 of an imageread/write head. In the illustrated structure, a plurality of lightreceiving elements 3 are integrally built in a plurality of drive ICchips 80A. With this structure, as compared with the above-describedembodiment in which a plurality of sensor IC chips 3A incorporating aplurality of light receiving elements 3 are provided separately from thedrive IC chips 80, the number of parts mounted on the substrate 4 can bedecreased so that the image read/write head can be manufactured withenhanced efficiency.

The specific details of the present invention may be modified in variousways apart from the above-described embodiments. For example, instead ofthe LEDs, a cold cathode tube may be employed as a light source.

1. An image read/write head comprising: a substrate which carries aplurality of light receiving elements, a plurality of printing elementsand a plurality of drive IC chips incorporating driving circuits forproviding drive control of the printing elements; a case mounted on thecase for surrounding the plurality of light receiving elements whileavoiding the plurality of printing elements; a transparent cover mountedto the case for contact with a document being transferred; a lightsource disposed in the case for illuminating the document; and aplurality of lenses disposed in the case for forming, on the pluralityof light receiving elements, an image of the document illuminated by thelight source; the image read/write head further including supportingmeans for supporting a platen roller disposed in facing relationship toat least either one of the transparent cover and the plurality ofprinting elements.
 2. The image read/write head according to claim 1,wherein the case and the supporting means are integrally molded ofresin.
 3. The image read/write head according to claim 1, wherein eachof the printing elements comprises a heating element, the substratebeing mounted to a heat sink plate, part of the heat sink plateproviding the supporting means.
 4. The image read/write head accordingto claim 1, wherein the plurality of light receiving elements, theplurality of printing elements and the plurality of drive IC chips aremounted on a same surface of the substrate.
 5. The image read/write headaccording to claim 4, wherein the light receiving elements areintegrally built in the drive IC chips.
 6. An image processing apparatuscomprising an image read/write head and a pair of platen rollers for adocument and a recording paper, respectively, the image read/write headincluding: a substrate which carries a plurality of light receivingelements, a plurality of printing elements and a plurality of drive ICchips incorporating driving circuits for providing drive control of theprinting elements; a case mounted on the case for surrounding theplurality of light receiving elements while avoiding the plurality ofprinting elements; a transparent cover mounted to the case for contactwith a document being transferred; a light source disposed in the casefor illuminating the document; and a plurality of lenses disposed in thecase for forming, on the plurality of light receiving elements, an imageof the document illuminated by the light source; the image read/writehead further including supporting means for supporting at least one ofthe paired platen rollers.
 7. The image processing apparatus accordingto claim 6, wherein each of the platen rollers is held by a memberprovided separately from the image read/write head; the supporting meansbeing fitted on a shaft portion of the recording paper platen roller forallowing pivotal movement of the image read/write head about the shaftportion; the image read/write head being biased by an elastic member ina pivotal direction for pressing the transparent cover against thedocument platen roller.
 8. An image read/write head comprising: asubstrate which carries a plurality of light receiving elements, aplurality of printing elements and a plurality of drive IC chipsincorporating driving circuits for providing drive control of theprinting elements; a case mounted on the case for surrounding theplurality of light receiving elements while avoiding the plurality ofprinting elements; a transparent cover mounted to the case for contactwith a document being transferred; a light source disposed in the casefor illuminating the document; and a plurality of lenses disposed in thecase for forming, on the plurality of light receiving elements, an imageof the document illuminated by the light source; the plurality of lightreceiving elements, the plurality of printing elements and the pluralityof drive IC chips being mounted on a same surface of the substrate; theimage read/write head further including a reflection preventing memberprovided separately from the case for collectively surrounding theplurality of light receiving elements and the plurality of drive ICchips.
 9. The image read/write head according to claim 8, wherein thereflection preventing member is black.
 10. The image read/write headaccording to claim 8, wherein the reflection preventing member includesmounting means for positioning and mounting the reflection preventingmember with respect to the case.
 11. The image read/write head accordingto claim 8, wherein the reflection preventing member includes an upperwall facing but spaced from the plurality of light receiving elementsand the plurality of drive ICs thicknesswise of the substrate, the upperwall including a slit for allowing light traveling through the pluralityof lenses to reach the plurality of light receiving elements, thereflection preventing member also including a plurality of elasticallydeformable side walls projecting from the upper wall toward thesubstrate into contact therewith.
 12. The image read/write headaccording to claim 11, wherein the substrate is black at least atportions in contact with the plurality of side walls.
 13. The imageread/write head according to claim 8, wherein the light source ismounted beside the plurality of light receiving elements on said surfaceof the substrate on which the plurality of light receiving elements aremounted; the reflection preventing member including a side wall forseparating the light source from the plurality of light receivingelements.
 14. An image read/write head comprising: a substrate whichcarries a plurality of light receiving elements, a plurality of printingelements and a plurality of drive IC chips incorporating drivingcircuits for providing drive control of the printing elements; a casemounted on the case for surrounding the plurality of light receivingelements while avoiding the plurality of printing elements; atransparent cover mounted to the case for contact with a document beingtransferred; a light source disposed in the case for illuminating thedocument; and a plurality of lenses disposed in the case for forming, onthe plurality of light receiving elements, an image of the documentilluminated by the light source; the image read/write head furtherincluding detecting means for detecting at least one of the document fedonto the transparent cover and a recording paper fed to a positionfacing the plurality of printing elements.
 15. The image read/write headaccording to claim 14, wherein the detecting means includes a movablemember having one end for contacting the document in a document transferpath, the movable member having another end for facing the light source;the movable member being so arranged that said another end blocks lighttraveling from the light source toward the transparent cover when saidone end is out of contact with the document, whereas said another endretreats to a position which does not block the light when said one endis in contact with the document.
 16. The image read/write head accordingto claim 14, wherein the detecting means includes a movable memberhaving one end for contacting the document in the document transferpath, the movable member having another end arranged in a light pathextending from the transparent cover to the plurality of light receivingelements; the movable member being so arranged that said another endblocks light traveling from the transparent cover toward the pluralityof light receiving elements when said one end is out of contact with thedocument, whereas said another end retreats to a position which does notblock the light when said one end is in contact with the document. 17.The image read/write head according to claim 14, wherein the detectingmeans includes a movable member having one end for contacting therecording paper in a recording paper transfer path, the movable memberhaving another end arranged in a light path extending from thetransparent cover to the plurality of light receiving elements; themovable member being so arranged that said another end moves between aposition for blocking light traveling from the transparent cover towardthe plurality of light receiving elements and a position which does notblock the light depending on whether or not said one end is in contactwith the recording paper.
 18. An image read/write head comprising: asubstrate which carries a plurality of light receiving elements, aplurality of printing elements and a plurality of drive IC chipsincorporating driving circuits for providing drive control of theprinting elements; a case mounted on the case for surrounding theplurality of light receiving elements but avoiding the plurality ofprinting elements; a transparent cover mounted to the case for contactwith a document being transferred; a light source disposed in the casefor illuminating the document; and a plurality of lenses disposed in thecase for forming, on the plurality of light receiving elements, an imageof the document illuminated by the light source; the plurality of lightreceiving elements, the plurality of printing elements and the pluralityof drive IC chips are mounted on a same surface of the substrate; theimage read/write head further including: supporting means for supportinga platen roller disposed in facing relationship to at least either oneof the transparent cover and the plurality of printing elements; areflection preventing member provided separately from the case forcollectively surrounding the plurality of light receiving elements andthe plurality of drive IC chips; and detecting means for detecting atleast one of the document fed onto the transparent cover and a recordingpaper fed to a position facing the plurality of printing elements.